GCN Circular 42278

Subject

GRB 251014A: Swift-BAT refined analysis

Event

GRB 251014A

Date

2025-10-15T01:35:52Z (2 days ago)

From

Rahul Gupta at NASA GSFC <rahul.gupta@nasa.gov>

Via

Web form

M. J. Moss (GSFC), E. Ambrosi (INAF-IASFPA),
S. D. Barthelmy (GSFC), R. Gupta (GSFC),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (U Tampa), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Parsotan (GSFC),
D. Sadaula (GSFC/UMBC), T. Sakamoto (AGU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 251014A (trigger #1403878)
(Ambrosi, et al., GCN Circ. 42238Loading...
 
 ).  The BAT ground-calculated position is
RA, Dec = 111.728, 6.420 deg which is 
   RA(J2000)  =  07h 26m 54.7s 
   Dec(J2000) = +06d 25' 10.7" 
with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 78%.
 
The BAT mask-weighted light curve shows a single peaked emission with total 
duration of less than 2 sec. T90 (15-350 keV) is 1.56 +- 0.24 sec (estimated error 
including systematics).
 
The time-averaged spectrum from T-0.07 to T+1.82 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 0.82 +- 0.70, 
and Epeak of 47.1 +- 9.2 keV (chi squared 60.50 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 2.3 +- 0.2 x 10^-07 erg/cm2
and the 1-sec peak flux measured from T-0.07 sec in the 15-150 keV band is
2.8 +- 0.2 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.90 +- 0.13 (chi squared 69.47 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level. 
 
The results of the batgrbproduct analysis are available at
https://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1403878